If you made a wooden base, couldn't you mill out a groove and just put a large piece of pipe in there? glue it if you really want to....

Let's see if I can ascii draft this here:

.. _
_/. \_
|.\_/.|
|......|
-------

The view is a cross-section, the hexagonal shape representing the pipe, the saddle being the wooden base. Throw a few coats of varnish on the wood for water resistance and I think it may work. There shouldn't be issues with the board touching the base given a large enough diameter pipe and the fact that you'd be falling off by then anyways. Plus you could round off the edges of top of the wooden base structure.
Sound idea? or am I way off my rocker?

ok had to edit, ignore the dots...for some reason the forum didn't like my formatting.
If you can't understand what I "drew" I can try to get a gif or jpeg up.

edit again...i see this idea has already been mentioned....
Would scrapyards be a good place to find rails? Or dumpsters behind machine shops?

Honestly as a welder, I'm going to say that is a lot of work. If you had a few pieces of metal you cut by yourself with a sawzall, or a skilsaw with a metal blade any welder should be able to throw together a simple single rail in less than an hour, and for a narrow box (12" or so) maybe 2 hours. If you are going super duper cheap and have the material, I don't think your idea would be a bad route. If you have any good welding shops you may be able to find something but at our shop we usually cut the stuff to pieces right when we get it. Check with a place that does a lot of commercial remodels, you might be able to find some type of rail for free.

If you have an older board that can become your 'backyard jib board', and that's all you're going to use it for, go ahead and fully file down the edges. Then you can use just about anything for your rails without worrying about catching your edges. For example, PVC pipes make a much less expensive box-edge than metal pipes.

Go to a local establishment, this includes a nearby library, hospital, senior citizens' center, etc. (any public venue basically) and find a nice rail, bonus points for finding a kink rail. Take a hacksaw to the base of the supports and then just strap that baby to the roof of your car. Remember to hang a red flag from the rail while transporting it or else a cop will pull you over (you need that red flag, it's the law).

Easy, and free.

Theft is not the answer and seriously what if it was your grandma needing to use that hand rail! I just went to my local hockey rink a few days ago and picked up enough (FREE) puckboard to build a box 13" * 8ft. 1/2 inch thick stuff..

P.s. You can still drop by the Library and read up on respecting your elders and community :P Sow good seeds and reap the good stuff!

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Tell the truth, even if it leads to your death. - For the truth will set you free.

Theft is not the answer and seriously what if it was your grandma needing to use that hand rail! I just went to my local hockey rink a few days ago and picked up enough (FREE) puckboard to build a box 13" * 8ft. 1/2 inch thick stuff..

P.s. You can still drop by the Library and read up on respecting your elders and community :P Sow good seeds and reap the good stuff!

me and my buddy are building a rail. we are making an a frame out of 2X4's the just screwing two 1-1/2" PVC pipes to the top 2X4. the pipes will hold because they are have a small diameter but with the same thickness of plastic. it will be light and under $50